Scenery object pop-up distances

Hi Guys,

 

In quite some of my addon airport sceneries the amongst others, (apron) objects, e.g. busses, tractors, passenger stairs, etc, only pop up and become visible at very short distances, e.g. while taxiing and/or approaching my (via ATC) assigned parking position. These distances are very variable and only seem and I repeat the word "seem", to be caused by BGL files made via the SCASM program. Disassembling such SCASM BGL files into their SCA versions is no problem nor are finding the texture files being called for but finding anything to do with possible pop-up distances within these SCA files, remains my big problem. However, I'm certainly no expert at this and need some help.

 

The texture files concerned are all DXT3 or DXT1, are mipped and have alpha channels.

 

Does anyone know where I should begin looking ?

 

Thanks in advance for any suggestions.

 

Hans

I am certainly no expert, and what I have to contribute may not help at all.

However, I make objects mostly for my own use, and I believe that the 'pop-up' distance is related to the size of the object, and that may be why the objects you describe having an issue with are very small objects.

For my own objects, I add a single, untextured,inverted triangular polygon below ground level, and I seem to be able to control the pop-up distance according to the size of the object and the size of the polygon.

This is entirely my own experience, and I would be happy to hear from anybody who has more knowledge.

Thanks for your reply David and your theory is certainly new for me. I'm now going to do some testing and will post my findings in this thread.

 

However, I must also point out beforehand that I cannot really imagine that something like this could be a structural problem of FS9 itself but as you point out, it certainly does concern small addon scenery objects only but definitely not all of them, hence me suspecting the different developer programming styles within their SCASM based BGL files.

 

Thanks again.

 

Hans

After a few hours of testing with XML based library objects randomly placed/positioned in one of my addon airport sceneries via the Abacus EZ program, it has turned out that the phyisical size of the objects do not make any difference. The normal sized objects and the (test) huge ones next to them, both appear and disappear at the same far too close and unrealistic distances from my taxiing or low flying aircraft.

 

The textures concerned were originally DXT1 but changing them to DXT3 (= larger) made no difference either.

 

Further ideas anyone ?

 

Regards

 

Hans

Hi,

 

https://www.flightsim.com/vbfs/showthread.php?72467-Objects-pop-up-as-I-get-closer-to-them

Reply #3.

 

https://www.avsim.com/forums/topic/51002-how-to-make-scenery-make-an-appearance-further-away/

Reply Scott967 and below.

 

Hope this helps a bit.

 

 

DDP.

I have a comment that is related to this discussion. What is your zoom level set at in virtual cockpit? I have found that 0.5 is the level that best reflects reality in spotting objects on the ground from the air. There are, definitely, some objects (particularly small planes) that appear at a shorter distance away than one would expect and I have never found a solution for this, or seen a definite solution in the forums. I make scenery objects, and in general larger ones get seen first, so "why" is an occasional mystery.

Hi Guys,

 

Thanks for all your reactions.

 

I opened an example texture of one of my far too close pop-up scenery objects via the program "DXTbmp" and all looked well. The size of this particular texture without mips was 129 Kb and with mips, 171 Kb. Via the "Preview" ---> DXT1 dropdown menu I was then able to see a series of 8 mipped sub-textures, ranging from the top very detailed one, right down to the last almost invisible "pin-point" one. All very normal and technically correct.

 

The only conclusion I can now come come up with is that the problem lies somewhere within it's XML based model (MDL) file, which calls for and processes this correctly mipped texture. However, to be able to search for and possibly fix such a problem, I would first need to be able to disassemble MDL files into something legible and also to afterwards be able to re-compile them back to their MDL files.

 

Can any of you experts please advise me on this, e.g. which program(s) I would be needing ?

 

Regards

 

Hans

Hi Guys,

 

In quite some of my addon airport sceneries the amongst others, (apron) objects, e.g. busses, tractors, passenger stairs, etc, only pop up and become visible at very short distances....

 

Hans

 

Hans, I think this is a function of what conditions were applied to the objects in question by the scenery designer. The object might have been created with a distance condition so that it appears only when the user is within a specific number of meters (ie. Distance to refpoint between 0 and X meters). Alternatively, the designer might have applied an empty LOD to the model to force it to vanish when a certain resolution is reached. I have used both methods in my scenery work. It takes a lot of work to avoid pop-up objects such as those you experienced with the airport in question.

 

Greg

Edited January 25, 2021 by gaputz

Roger,

 

I tried what you suggested, in VC mode with a zoom of 0.5 or less and the objects concerned do seem the pop up/disappear at greater distances but this does tend to make the whole external scenery look too far away and therefore less realistic. The same also applies when in 2D mode with the same negative zoom levels. Moreover, this is not the structural solution, if there is one, I was really looking for.

 

Thanks anyway for your suggestion and I will certainly keep it in mind.

 

Hans

Greg,

 

Thanks for your reaction.

 

I'm certainly no scenery designer myself but somewhere deep inside me I just cannot imagine that a scenery designer/developer would purposely dispose of or decrease the positive effects of the "standard" mipmap technology and especially when this should specifically be used to enhance frame rates.

 

Oh well, I'll see where this thread ends and if one or more of you experts will go as far as to say that my problem is impossible to fix in the way that I had imagined, then so be it and I'll then go searching for another problem. LOL.

After all, as a result of all these covid lockdowns/curfews, etc. there's not much else to do, apart from trying to enhance my "one and only" FS9 even further.

 

Regards

Hans

Have you tried maxing all the scenery sliders in Options to see if any of those have any effect?

Roger,

 

I tried what you suggested, in VC mode with a zoom of 0.5 or less and the objects concerned do seem the pop up/disappear at greater distances but this does tend to make the whole external scenery look too far away and therefore less realistic. The same also applies when in 2D mode with the same negative zoom levels. Moreover, this is not the structural solution, if there is one, I was really looking for.

 

Thanks anyway for your suggestion and I will certainly keep it in mind.

 

Hans

 

Hans,

 

In my experience that is how the ground scenery appears in real life, so I would say it is more realistic, not less. Even if you are only at 3,000 feet or so, anything on the ground that you can see is at least a kilometre away. If you are standing on the ground how big is a car at a range of 1 kilometre? I don't intend to push the idea and you should do whatever you prefer; it is just my opinion.

 

Greg seems to have explained it well why objects pop up suddenly.

Roger,

 

For me another very steep learning curve during the running of this thread and yes, Greg's explanation immediately put me off the thought that a model (MDL) file could simply be disassembled into legible (possibly XML) text, then edited and finally "re-compiled" back into the MDL file. More or less like with BGL files.

 

Nope, I found another thread on this same subject somewhere and inwhich Scott exclaimed that what I really wanted to do was in fact structurally protected and that only the original author of the scenery would be able to do any editing, etc. So, I sent the author an e-mail, hoping that he is still active and am now awaiting his respons.

 

==========

 

Tom,

 

Because my question/problem was not a structural FS9 issue but only a very specific detail, I did not look at any general slider positions.

 

Anyway, thanks for your reaction.

 

Stay healthy to all.

 

Hans

BTW, you can do some editing of objects using ModelConverterX, but only for personal use without the author's permission.

 

The only other thing I could think of would be to make the bounding box bigger using MDL Tweaker, but if crash is turned on for that object you will run into it way before you actually hit it.

Tom,

 

I immediately downloaded ModelConverterX and had a quick look through it's PDF file but apart from needing about 7 university degrees to be able to fully understaand all it's functions, I strongly got the impression that, as it's name already implies, it's main function is converting certain files from one FS version to another or in any case, something of that nature.

 

However, on the very last pages (108 and 109, section 11.3) of the ModelConverterX.pdf file, I did find something which probably knocks the bottom out of my simple idea that it's the direct DISTANCE to a small scenery object, which decides which of the 8 LODs in a correctly mipped texture file, will be rendered.

 

It explains something about so called "Drawcalls" for small scenery objects, e.g. my baggage carts, and the frame rate enhancing method of combining all necessary texture parts into a single texture (BMP) file, as opposed to multiple texture files, each containing those parts separately. Well, my baggage cart texture example is clearly such a "drawcall" version. Correctly mipped. Yes, ...... BUT ......

 

At the top of page 109 it says: "There is one catch to this drawcall batching and that is, when enabled, it will prevent the levels of detail from working". Oops !!

I certainly do not have 7 university degrees but from this I now understand that I will need to get used to the fact that quite some scenery developers use these drawcall textures for the explicit reason of enhancing frame rates and that the short range small scenery object pop-ups are just something we simmers must learn to live with.

 

The explanation goes further about the relation between object sizes, distances and LOD pixel values, which only now causes me to further understand what David above, has posted about object sizes and empty polygons.

 

Anyway guys, thanks to all of you for a very good and educational thread.

 

Hans

Drawcall Batching really became common with the introduction of FSX; I don't know if it has any effect in FS9 (I've never seen anyone test that). So most people back in FS9 days dealt with LODs for frame rate improvement.

 

While the main purpose of MCX is to convert models to other formats, Arno has added lots of other features that allow one to add or subtract LOD models, remove certain parts of objects, and merge objects together into a single object. So it's pretty flexible at this point.

 

Finally, I don't think that MCX can change the bounding box of FS9 models (although I've never tried), and anyway I think it requires the separate MDL file that is then compiled directly into a library BGL file using a tool like Library Maker. MCX will always (?) recompile MDL files upon Export, and thus any tweaks would be lost. It can Export the MDL file from a library BGL file, though, for tweaking later.